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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the E7 and E9 ECM connectors.

      Standard: 

      ECM (+B VOLTAGE)

      Tester Connection Specified Condition
      +B (E9-1) - E1 (E7-1) 9 to 14 V
    Fig 1: Inspecting ECM (+B Voltage)
    G04676501Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE   ) 

    NG: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E7 ECM connector.
    2. Check the resistance between the wire harness side connector.

      Standard (Check for open): 

      ECM - BODY GROUND

      Tester Connection Specified Condition
      E1 (E7-1) - Body ground Below 1 Ω
      Fig 2: Checking Harness And Connector (ECM - Body Ground)
      G04676502Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the E7 and E9 ECM connectors.

      Standard: 

      ECM (IGSW VOLTAGE)

      Tester Connection Specified Condition
      IGSW (E9-9) - E1 (E7-1) 9 to 14 V
    Fig 3: Inspecting ECM (IGSW Voltage)
    G04676503Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to step   6 

    NG: Go to next step. 

  4. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the driver side J/B.
    2. Check for continuity in the IGN fuse.

      Standard: Continuity 

    3. Reinstall the IGN fuse.
      Fig 4: Checking Fuse (IGN Fuse)
      G04676504Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED IGN FUSE, AND REPLACE IGN FUSE 

    OK: Go to next step. 

  5. INSPECT IGNITION OR STARTER SWITCH ASSY 
    1. Disconnect the I18 ignition switch connector.
    2. Measure the resistance between the connector terminals shown in IGNITION OR STARTER SWITCH ASSY  .

      Standard: 

      IGNITION OR STARTER SWITCH ASSY

      Switch Position Tester Connection Specified Condition
      LOCK All Terminals 10 kΩ or higher
      ACC 2-3 Below 1Ω
      ON 2-3, 2-4, 6-7 Below 1 Ω
      START 1-2, 2-4, 6-7, 6-8 Below 1 Ω
      Fig 5: Inspecting Ignition Or Starter Switch Assy
      G04676505Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the ignition switch connector.

    NG: REPLACE IGNITION OR STARTER SWITCH ASSY 

    OK: CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION SWITCH - ECM) 

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the E7 and E9 ECM connectors.

      Standard: 

      ECM (MREL VOLTAGE)

      Tester Connection Specified Condition
      MREL (E9-8) - E1 (E7-1) 9 to 14 V
      Fig 6: Inspecting ECM (MREL Voltage)
      G04676506Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE ECM (See  REPLACEMENT  ) 

    OK: Go to next step. 

  7. CHECK FUSE (EFI FUSE) 
    1. Remove the EFI fuse from the engine room R/B.
    2. Check for continuity in the EFI fuse.

      Standard: Continuity 

    3. Reinstall the EFI fuse.
      Fig 7: Checking Fuse (EFI Fuse)
      G04676507Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED EFI FUSE, AND REPLACE EFI FUSE 

    OK: Go to next step. 

  8. INSPECT EFI RELAY 
    1. Remove the EFI relay from the engine room R/B.
    2. Check for continuity in the EFI relay.

      Standard: 

      EFI RELAY

      Tester Connection Specified Condition
      1 - 2 Continuity
      3 - 5 No continuity
      3 - 5 Continuity
      (Apply battery voltage to terminals 1 and 2)
      Fig 8: Inspecting EFI Relay
      G04676508Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the EFI relay.

    NG: REPLACE EFI RELAY 

    OK: Go to next step. 

  9. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM, EFI RELAY - BODY GROUND) 
    1. Check the harness and connector between the EFI relay and ECM.
      1. Remove the EFI relay from the engine room R/B.
      2. Disconnect the E9 ECM connector.
      3. Check the resistance between the wire harness side connectors.
        Fig 9: Identifying EFI Relay
        G04676509Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for open): 

        EFI RELAY AND ECM (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Engine room R/B (EFI relay terminal 1) - MREL (E9-8) Below 1 Ω

        Standard (Check for short): 

        EFI RELAY AND ECM (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Engine room R/B (EFI relay terminal 1) or MREL (E9-8) - Body ground 10 kΩ or higher
        Fig 10: Checking Harness And Connector (EFI Relay - ECM, EFI Relay - Body Ground)
        G04676510Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Reinstall the EFI relay.
      5. Reconnect the ECM connector.
    2. Check the harness and connector between the EFI relay and body ground.
      1. Remove the EFI relay from the engine room R/B.
      2. Check the resistance between the wire harness side connector and body ground.

        Standard (Check for open): 

        EFI RELAY AND BODY GROUND

        Tester Connection Specified Condition
        Engine room R/B (EFI relay terminal 2) - Body ground Below 1 Ω
      3. Reinstall the EFI relay.

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    NG: CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL +B OF ECM - BATTERY POSITIVE TERMINAL) 

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